Engine starting apparatus



Oct. 14, 1952 P- L. SCHNEIDER ENGINE STARTING APPARATUS {Filed Oct. 28.1948 INVENTOR PAUL L. SCHNEIDER HIS ATTORNEYS Patented Oct. 14, 1952ENGINE STARTING APPARATUS Paul L. Schneider, Anderson, Ind., assignor toGeneral Motors Corporation, Detroit, Mich., a

corporation of Delaware Application October 28, 1948, Serial No. 57,056

4 Claims.

This invention relates to engine starters and its object is to provideslow initial movement of the starting motor pinion to facilitate meshingthereof with the engine flywheel gear and to withhold the application ofcurrent for engine starting to the starting motor until after the gearshave been completely meshed.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawing, wherein a preferred embodiment of the present invention isclearly shown.

In the drawing:

Fig. 1 is a diagram illustrating the starter.

Fig. 2 is a fragmentary, longitudinal, sectional view showing a startingmotor and gearing for connecting it with the engine flywheel ear.

Fig. 3 is a sectional view on line 33 of Fig. 2.

The starting motor In (Fig. 2) has a field frame H secured to plate l2which is mounted on a housing l3 provided by the engine. The armature Mof the motor is connected with an armature shaft l5 connected with agear 16 meshing with a sliding gear 11 connected through a gear hub Ilawith a driving member l8 of a one-way roller clutch having a drivencylinder I!) connected with the pinion which is mounted upon a rod 2isupported by the engine frame and is movable into mesh with the engineflywheelgear 22. When clutch member l8 rotates tain the springs 24.

The assembly of gear I! and overrunning clutch is normally maintained inthe position shown in Fig. 2 by a, spring 32 confined under compressionbetween a cup 33 engaging the rod 2| and surface 35 of a plunger 36connected with gear hub Ha. Spring 32 maintains the pinion 20 spacedfrom gear 22 and gear H. An oil'seal 31 minimizes escape of oil from thehousing which encloses the gears and the entrance of dirt and moisturetherein.

Plunger 36 is engaged by a lever 39 (Fig. 1)

-pivoted at 40 and having an arm 4| connected 'by a pin 42'with a link43 connected by a pin 44 with a solenoid armature 45. Solenoid armature'45 is supported for horizontal sliding movement tion as it'moves towardthe gear 22.

2 toward a fixed core 46 by non-magnetizable tube 41 supported by amagnetizable shell 48 which supports the core 46. Armature is engageablewith a rod 49 which extends through a sleeve 5| insulatingly sup-portinga contact 50, a washer '53, a spring 54 and a, C-washer 55 received by agroove in rod 49 and retained therein by the spring 54. Spring 54 urgesthe sleeve 5| toward a split ring 56 snapped into groove of rod 49. Aspring 51 which engages the sleeve 5| urges the washer 55 against thecore 46 and maintains the contact 50 normally out of engagement withcontacts and 61 which are connected with a resistance 62.

Contact 60 is connected with magnet coil 63 of larger wire and magnetcoil 64 of finer' wire which, respectively, are connected with contact-6l and-ground. Contact 60 isoonnected with switch '10 is energizedandcontact 12 connects contacts H and 13. Current flows fromthe'battery towinding 64 andground return to the battery and also'through winding 63,starting motor l0 and ground return to the battery and throughresistance '62, the starting motor l0 and ground return to the battery.Armature 45 moves left thereby moving the pinion 20 into engagement withthe flywheel gear 22. While the pinion '2il'ismoving toward the gear22,it is rotating relatively slowly since the resistance 62 and the coil63 in parallel therewith pass current to the motor In 'suificient for itto develop a torque'which overcomes frictional resistance but notsufiicient to rotate the pinion '20if it abuts the gear 22. If there isno abutmentfollowing the first closing of switch 16, the'armature 45continues its left movement to move the pinion 20 into mesh with thegear 22 and to cause the contact 59 to engage contacts 60 and 61 therebyshorting resistance 62 and coil 63 and'causing cranking current to beapplied to the motor l0. Coil 64 alone will maintain contact '50 inengagement with contacts '60 and 6| against the action of spring 51 (attheleftofth'e contact 50) and spring 32 in the plunger 36'.

If gear tooth abutment'follows thefirst closing of switch 16, it isreleased to allow spring 32"t0 move the pinion 20 away from the gear 22and the switch 16 is closed again. The pinion 2'0 rotates slowly againto a different angular posi- Generally a second closure of switch 16will result in location of the pinion 20 in meshing registration withthe gear 22 by the time the pinion has moved into contact with the gear.

Contact 50 does not engage contacts 60 and BI until after pinion 20 hasbeen substantially fully meshed with gear 22. Therefore the motor lcannot develop cranking torque until after the gears have been meshed.The motor I0 cranks the engine; and, when the engine becomesselfoperative, it drives the pinion 20 faster than it can be driven bythe motor 10, and pinion 20 overruns the gear I! by virtue of theoverrunning clutch.

The engine having been started, the switch 16 is released and thesolenoid switch opens to disconnect the battery from the motor and thesolenoid windings B3, 64.

If, after meshing the pinion with the engine gear and moving the contactinto engagement with contacts 60 and GI the engine does not start andthe motor i0 is stalled, the switch 16 is opened to effectdeenergization of the solenoid so that spring 57 is effective toseparate contact permitted because lever 39 can move clockwise althoughplunger 36 is fixed. The short circuit of resistance 62 having beeninterrupted, the torque of motor [0 i so reduced that spring 32 is ableto effect retraction of the pinion from the engine gear.

A manually operated switch 80 may be placed in the circuit between thebattery and the solenoid switch 10 in order to open the circuit afterthe engine is running thereby preventing operation of the starter byinadvertent closing of switch 16.

While the embodiment of the present invention as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. Engine starting apparatus comprising an electric motor, a pinionnormally spaced from a gear of the engine to be started and movable intomesh therewith, a spring for retracting the pinion from the engine gearand for yieldingly maintaining it in said spaced relation, anoverrunning clutch connecting the motor and pinion, a battery, asolenoid having an armature and a main armature attracting coil and anarmature holding coil, means for transmitting motion from the armatureto the pinion to cause it to mesh with the engine gear, a circuitbetween terminals of the battery and including a control switch in Iseries with two circuits in parallel one of which includes the holdingcoil and the other of which includes the motor and the main coil and aresistance in parallel with the main coil, said resistance and main coiltogether passing to the motor current sumcient only to cause it torotate the pinion while out of contact with the engine gear, and aswitch which is operated by the solenoid armature to short-circuit themain coil and resistance only after the pinion has been substantiallyfully meshed with the engine gear.

2. Engine starting apparatus comprising an electric motor, a pinionnormally spaced from a gear of the engine to be started and movable intomesh therewith, a spring for retracting the pinion from the engine gearand for yieldingly maintaining it in said spaced relation, anoverrunning clutch connecting the motor and pinion, a battery, asolenoid having a plurality of windings and an armature, means fortransmitting motion from the armature to said pinion to move the latterinto mesh with the engine gear, a circuit for the starting motorincluding the battery, a manually closed switch, a resistance and aconnection from the resistance to said motor, said resistance having avalue such that when current flows through said circuit to the motor themotor develops a torque suflicient only to turn the pinion while it isdisengaged from the engine gear, said solenoid windings being connectedto said starting motor circuit between the manually operable switch andthe resistance whereby the solenoid windings are subject to the fulleffect of the battery to engage said pinion with the engine gear, aswitch operable when the inion is fully engaged with said gear to shortcircuit said resistance and to connect the motor directly with saidbattery, and a connection from one of said windings to said startingmotor circuit between said last named switch and the motor whereby oneof said windings is short circuited when said last named switch isclosed.

3. Engine starting apparatus comprising an electric motor, a, pinionnormally spaced froma gear of the engine to be started and movable intomesh therewith, a spring for retracting the pinion from the engine gearand for yieldingly maintaining it in said spaced relation, anoverrunning clutch connecting the motor and pinion, a battery, asolenoid having a plurality of windings and an armature, means fortransmitting motion from the armature to said pinion to move the latterinto mesh with the engine gear, a circuit for the starting motorincluding the battery, a manually closed switch, a resistance and aconnection from the resistance to said motor, said resistance having avalue such that when current flows through said circuit to the motor themotor develops a torque sufiicient only to turn the pinion while it isdisengaged from the engine gear, said solenoid windings being connectedto said starting motor circuit between the manually operable switch andthe resistance whereby the solenoid windings are subject to the fulleifect of the battery to engage said pinion with the engine gear, aswitch operable when the pinion is fully engaged with said'gear to shortcircuit said resistance and to connect the motor directly with saidbattery, a connection from one of said windings to said starting motorcircuit between said last named switch and the motor whereby one of saidwindings is short circuited when said last named switch is closed, and aconnection from the other of said windings to ground whereby said lastnamed winding is rendered effective to hold the pinion in engagementwith the gear after the other of said windings is short circuited.

4. Engine starting apparatus comprising an electric motor, a pinionnormally spaced from a gear to the engine to be started and movable intomesh therewith, a spring for retracting the inion from the engine gearand for yieldingly maintaining it in said spaced relation, anoverrunning clutch connecting the motor and pinion, a battery, a soleoidhaving a pluralityof windings and an armature, means for transmittingmotion from the armature to said pinion to move the latter into meshwith the engine gear, a circuit for the starting motor including thebattery, a manually closed switch, a. resistance and a connection fromthe resistance to said motor, said resistance having a value suchthatwhen current flows through said circuit to the motor the motordevelops a torque suiiicientv only to turn the pinion while it isdisengaged from the engine gear, said solenoid windings being connectedto said starting motor circuit between the manually operable switch andthe resistance whereby the solenoid windings are subject to the fulleffect of the battery to engage said pinion with the engine gear, aswitch operable by the magnet armature, when the latter has moved to aposition to effect engagement of said pinion with the engine gear, toshort circuit said resistance and to connect the motor directly withsaid battery, and a connection from one of said windings to saidstarting motor circuit between said last named switch and the motorwhereby one of said windings is short circuited when said last namedswitch is closed.

PAUL L. SCHNEIDER.

6 REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

